257120621568 has 88 divisors (see below), whose sum is σ = 761466968960. Its totient is φ = 85706864640.

The previous prime is 257120621551. The next prime is 257120621609. The reversal of 257120621568 is 865126021752.

257120621568 is a `hidden beast` number, since 2 + 5 + 7 + 1 + 20 + 62 + 1 + 568 = 666.

It is a super-2 number, since 2×257120621568² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4622248 + ... + 4677543.

Almost surely, 2^257120621568 is an apocalyptic number.

It is an amenable number.

257120621568 is an abundant number, since it is smaller than the sum of its proper divisors (504346347392).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

257120621568 is an equidigital number, since it uses as much as digits as its factorization.

257120621568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9299820 (or 9299796 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 45.

The spelling of 257120621568 in words is "two hundred fifty-seven billion, one hundred twenty million, six hundred twenty-one thousand, five hundred sixty-eight".